Spinning of textile yarns



July 14, 1970 J. M. SHEPHERD 3,520,122

SPINNING 0F TEXTILE YARNs Filed Sept. 8. 1967 2 Sheets-Sheet 1 ar WLM y? 7&2

2 Sheets-Sheet 2 J. M. SHEPHERD SPINNING OF TEXTILE YARNS July 14, 1910 Filed Sept. 8, 1967 United States Patent O1 hee 3,520,122 Patented July 14, 1970 U.S. Cl. 57-58.89 t 12 Claims ABSTRACT F THE DISCLOSURE An open-end fiber spinning apparatus in which the inner surface of the spinning rotor is provided with a fiber collecting circumferential groove. The -groove is needle free and projection free and converges to a sharp point in which fibers are deposited and compacted before being twisted into a yarn.

The present invention relates to open end spinning apparatus and is particularly concerned with apparatus of the type in which twisted yarn is formed by continuously depositing discrete fibres on a fibre-collecting inner surface of a spinning rotor, continuously removing them from the surface to form the tail end of a yarn with respect to which the rotor rotates and drawing off the continuously formed twisted yarn.

An object of the present invention is to provide openend spinning apparatus of this type 'which will produce an improved yarn.

According to the invention, there is provided open-end spinning apparatus comprising a hollow spinning rotor having an inner surface concentric with respect to the rotary axis of the rotor, said surface being provided with a libre-collecting circumferential groove free from needles or other projections and in which discrete fibres are deposited and compacted before being twisted into a tail end of yarn and drawn off as a twisted yarn.

Preferably, the inner surface of the rotor extends gradually to a region of maximum diameter and then reduces in diameter either abruptly or gradually, and the groove is formed in the surface at the region of maximum diameter.

Two embodiments of the invention will now be described by way of example with reference to the accompanying drawings in which,

FIG. 1 is a schematic diagram of an open-end spinning apparatus according to a first embodiment of the invention,

' FIG. 2 is a diametral section of part of the spinning rotor of the open-end spinning apparatus shown in FIG. 1, and

FIG. 3 is a diametral section of an alternative rotor for use in the apparatus shown in FIG. l.

With reference first to FIG. 1, fibres from delivery rollers 11 and 12 of a drafting system 13 are fed to the inlet end of a fibre feed tube 14 down Iwhich they are drawn in an airstream and deposited in the form of a ring of libres under the action of centrifugal force into a groove 15 on an inner surface of a hollow spinning motor 16 arranged for rotation about a vertical axis. The rotor 16 has an open uppermost end which is partially closed by a cover plate 17 which also serves as a cover plate for a housing 18 within which the rotor 16 is mounted. The cover plate 17 is arranged to receive the fibre feed tube 14 which passes through it and which terminates at a position close to the fibre-collecting inner surface 15 of the rotor 16. The cover plate 17 is, in addition, formed with a central opening into which is fitted a vertically arranged yarn delivery tube 19 through which the formed yarn 20 from the rotor 16 is continuously passed upwardly and out of the rotor 16 and the housing 18. The yarn 20 is withdrawn from the yarn delivery tube 19 by a pair of yarn delivery rollers 21 and 22 mounted above the tube 19 and the yarn 20 is passed by these rollers to a yarn package 23 upon which it is wound with the aid of a take-up drum 24. The rotor 16 is carried by a shaft 25 rotatably mounted in a bearing housing 26 and arranged to be driven by a belt drive comprising a driving belt 27 and a belt pulley 28.

With reference now to FIG. 2, the rotor 16 is so constructed that the inner surface 15 extends downwardly and outwardly to form a first frusto-conical portion 29 and then downwardly and inwardly to form a second frusto-conical portion 30. In accordance with the invention, a V-shaped groove 31 is formed at the junction between the two frusto-conical portions 29 and 30, the included angle being 30 and the depth of the groove being sufficient to contain the whole of the cross section of the fibre ring, and the arrangement is such that in operation discrete fibres are fed to the rotor 16 and deposited in the groove 31 where they are compacted to form a ring of fibres and then withdrawn to form the tail end of a twisted yarn in known manner.

In commencing a spinning operation, a seed yarn is initially fed into the top end of the yarn delivery tube 19 and through the tube into the rotor 16 until its end contacts the fibre-collecting groove 31 of the rotor 16. Fibres from the delivery rollers 11 and 12 are fed to the libre feed tube 14 and are sucked down the feed tube 14 in an airstream into the rotor 16. The rotor is arranged to rotate at very high speed in excess of 15,000 r.p.m. and the fibres fed to the rotor 16 are deposited in the groove 31 by the action of centrifugal force and form a fibre ring therein. The yarn delivery rollers 21 and 22 are then started so as to withdraw the seed yarn, whereupon spinning of yarn commences, the yarn being drawn up the delivery tube 19 and from the upper end of the tube in a vertical path to the yarn delivery rollers 21 and 22 from which the yarn is delivered to a take-up package 23.

In an alternative embodiment of the invention, the rotor 16 shown in FIGS. 1 and 2 is replaced by a rotor 32 illustrated in FIG. 3. The inner surface of the rotor 32 is concentric with respect to the rotary axis of the rotor and extends first outwardly and downwardly to form a frusto-conical portion 33 and then radially inwardly to form a fiat base portion 34 lying in a plane at right angles to the rotary axis of the rotor. In accordance with the invention, a V-shaped fibre-collecting circumferential groove 35 is formed along the junction between the frusto-conical portion 33 of the surface and the base portion 34.

In operation, fibres are fed to the inner surface of the rotor 32 and deposited in the groove 35 where they are compacted and then withdrawn to form in known manner a tail end of twisted yarn.

It has been found that the yarn produced by withdrawing fibres from the groove 31 of the rotor 16 and from the groove 35 of the rotor 32 is stronger than yarn formed in rotary spinning chambers of the same shape but without a groove.

The groove may, if desired, be of any other shape which provides an increase in the diameter of the inner surface of the chamber and in the fibre-collection region thereof.

What I claim as my invention and desire to secure by Letters Patent is:

1. An open-end fiber spinning apparatus comprising a hollow spinning rotor having an inner surface concentric with respect to the rotary axis of the rotor, said surface being provided with a fiber-collecting circumferential groove lbeing needle-free and projection-free, the side Y 3 wallsv of said groove converging to asubstantially sharp point in which discrete fi'bers are deposited and compacted before being twisted into a tail end of the yarn and drawn o f as a twisted yarn.

2. Apparatus according to claim 1, wherein said inner surface of the rotor has a region of maximum diameter, extends gradually to the region of maximum diameter on one side thereof and then reduces in diameter either abruptly or gradually on the other side of` said region and wherein said groove is formed in the surface at the region of maximum diameter, said groove including a substantially V shaped end portion.

3. Apparatus according to claim 2, wherein said portion is said converging side walls which compact fibres entering said portion and is of suficient depth to contain the compacted bre, layers within said portion.

4. Apparatus according to claim 3, wherein the angle included by the said converging side walls is not greater than 35. k t

5. Apparatus according to claim 2, wherein said inner surface of the rotor comprises a first frusto-conical portion on one side of the region of maximum diameter and increasing in diameter thereto and a second frusto-conical portion on the other side of said region of maximum diameter and reducing in diameter therefrom, and wherein said groove is formed at the junction of the two portions.

6. Apparatus according to' claim 5, wherein one of said side walls of said groove is inclined to and lies on one side of a plane passing through the junction of the two frusto-conical portions and wherein the otherof said side walls of the groove is inclined to and lies on the other side of said plane.

7. Apparatus according to claim 6, wherein the plane containing the junction of said Vfrusto-conical portions contains the intersection of the surfaces in which said side walls of said groove4 portion lie.

8. Apparatus according to claim 2,.wherein the inner surface of the rotor comprises a first frusto-conical -portion on one side of the regio'n of maximum diameter and increasing in diameter thereto, and at the region of maximum diameter a fiat base portion lying in a plane at right angles to the rotary axis of the rotor, and wherein said circumferential groove is formed at the junction of the said first portion and thesaid base' portion.

9. Apparatus according to claim `8, wherein one side Wall of said groove portion is formed by the said base portion.

10. Apparatus according -to claim 9, wherein said groove portion is formed with converging side walls to compact fibres entering the groove and is of sufficient depth to contain the compacted fibre layers within the groove. 'A v 11. Apparatus according to claim 10, wherein the angle included by the said converging sidel` walls is not greater than 35.

12. -Gpen-end spinning apparatus comprising a hollow spinning rotor having an inner surface concentric relative to the rotational axis of the rotor, said surface being provided with a fiber-collecting circumferential groove References Cited UNITED STATES PATENTS 3,324,642 `6/1967 Meimberg et al 57-58.95

JOHN PETRAKES, Primary Examiner Dated J. M. SHEPHERD July llt, 1970 in the above-identified patent `and that said Ltters Patent are hereby corrected as shown below:

Cancel sheet 2 of the drawings. This "sheet 2 is Figs. 1 and 2 Qf U:S. Patent No. 3,`8l,129 and does not belong with this Patent (3,520,122).

Slhi. im,

SEALED Nov 3 l s, i

mw E. 1 omiesionor of P tants 

